ethyl 4-formyl-2,5-dimethyl-1H-pyrrole-3-carboxylate

diethyl 5-[(4-ethoxycarbonyl-2,5-dimethyl-1H-pyrrol-3-yl)methyl]-3-methyl-1H-pyrrole-2,4-dicarboxylate

ethyl 4-formyl-1,2,5-trimethylpyrrole-3-carboxylate